Preparation, Magnetic and Electric Properties of (110)-Oriented Ordered Fe_2-xTi_xO₃ Thin Films

Abstract

Ilmenite-hematite solid solution (Fe_2-xTi_xO₃) is known to have unique magnetic and electric properties. It is one of the candidates for novel magnetic semiconductors with the high Curie temperature (Tc). The carrier type of Fe_2-xTi_xO₃ is controllable by changing the Ti content x. In order to fabricate the semiconductor devices, epitaxial thin films having good crystallinity with precise control of their carrier type are required. We have already succeeded in preparing well-crystallized epitaxial Fe_2-xTi_xO₃ (x=0.7) films on α-Al2O3 (110) single-crystalline substrates by reactive helicon plasma-sputtering technique. The films are expected to have n-type conduction, while the films having the higher Ti content could be p-type conduction. In this research, we tried to prepare (110)-oriented solid solution films over a wide composition range.